METHOD AND APPARATUS FOR MANUFACTURING OF A LUMINOUS INDICATOR BOARD WITH OPTICAL FIBRE

Abstract: A method to make a display board (8) illuminated by light fibres (11), in which method a display board illustrating different figures is produced by arranging the illuminating ends of the light fibres into wanted spots onto the surface of the display board. Board perforation and feeding the light fibres (11) into holes (13) as well as cutting off the light fibres are carried out in successive steps using the same coordinate controlled punching and feeding device (4, 5, 6, 7).

Description: METHOD AND APPARATUS FOR MANUFACTURING OF A LUMINOUS INDICATOR BOARD WITH OPTICAL FIBRE The invention relates to a method according to patent claim 1 and to making a display board illuminated with light fibres according to patent claim 8. Previously known are display boards accomplished with light fibres, where the light fibres have been, by hand, threaded into holes drilled in advance, fastened into the holes and cut to size so that they reach from the light source, often placed behind the board, to the board. Production of such boards is often time-taking and expensive, because the number of light fibres to be handled amounts to hundreds. Further, the worker is exposed to glue vapor in fixing the light fibres to the board. The method and apparatus according to this invention solve the actual problem in a surprising way and the invention is characterized in what is presented in the enclosed patent claims. The major advantages of this invention can be considered the the level of automation, which is reached by using a locally steered transfer gear, as for instance a coordination table, the transfer motions of which can be programmed. Thus it is possible to drill with the apparatus holes for any illuminated figure in the board and repeat the movements in order to in¬ stall the ligth fibres into respective holes; By means of an adhesive film to be fixed on the board underside, each light fibre can be secured by simple means each into its matching hole; As light fibre feeding apparatus the wire feeding device of a wire welding machine applicable to the procedure can be applied without changes; For light fibre cutting a simple short-motion electric device can be used. In the following the invention is disclosed with reference to the enclosed drawing, where Fig. 1 is a diagonal view of a device placing the light fibres onto the display board. Fig. 2 a feeding and cutting device. Fig. 3 is a sectional and enlarged view of cutting. Figure 1 shows a coordination table formed by means of longi¬ tudinal guides 1 and transverse guides 2, on which table attaching part 3 can be moved above display board 8. Previ¬ ously, the coordination table is known in itself and it includes programming devices, by means of which movements and stops to be done with the apparatus on the X-Y level can be determined in advance. Accordinly, the motions of attachment part 3 can be programmed in advance on board 8 surface, in order to drill holes 13, for instance. Holes 13 are drilled so that the wanted illuminated figure is produced when the light fibre ends are put into the holes. In the second stage the same holes are travelled over again while feeding the light fibres into them. Accuracy of the repeated procedure is re¬ tained if the board is not released from its brackets during and between different steps. In the picture, there is on attachment part 3 a light fibre feeding and cutting device with a light fibre reel 5 and under protecting cap 4 the rotating motors reguired for reel 5 rotation, if it is necessary. On the underside of attachment part 3 there is a feeding tip 7, a cutting blade and a blade moving device 7. Figure 2 illustrates the feeding procedure and cutting. As light fibre feeding device the wire feeding device of a wire welding machine eguipped with feeding rolls 14 is used. The feeding device body 15 is partly cross-cut. Light fibre 11 comes from reel 5, travels through feeding tip 6 and goes through the board 8 hole 13 and is fed as long as the wanted length of it extrudes from display board 8 underside. When a drill has been fastened to the apparatus in place of feeding tip 6 in order to make the holes and when the same X-Y level transfers are done for the second time, the light fibre threaded through the feeding tip hits hole 13, exactly. When the hole is drilled an adhesive film 10 fastened on the board underside, the light fibre bursts through the film forming a collar section into it and the glue inside the collar adheres to the light fibre, becomes cured and secures the light fibre into the hole. Electric cutting device 7 cuts off the light fibre before the apparatus shiftes over to the next hole. The length of the light fibre can also be programmed in the automation system of feeding and transfer. Figure 3 illustrates cutting head 6 in a bigger scale and the groove in it for blade 9 motion. The cutting blade can, of course, be placed still much closer to the board surface. In tip 6 there is a groove at least in blade 9 inlet direction so tha cutting may work and the tip portion would steer the light ibre as far as possible toward hole 13. It is also easy to add a device into the tip, which after cutting would push the light fibre ever closer to the board surface, for instance. In one embodiment the attachment part 3 can be both a feeding tip 6 and a hole drilling device at the same side by side. Thereby, one of them or both can be in a seprate transfer gear and can then be shifted to focusing position in attachment part 3 so that they are working in proper X-Y level position. Another embodiment is that both of them have a fixed position in attachment part 3, but the X-Y transfer automation knows the difference between their fixed coordinates and observes it when the apparatus is moved to the drilling position and the light fibre feeding position. On using adhesive film it is advantageous to do the holes at first and then apply the adhesive film on the board underside and finally feed the ligth fibre into the holes. When the illuminated figure is formed of a number of fibres of different colors or fibres divided into groups of one color illuminating at different times, it is advantageous to cut the fibres into bundles of one group each, which have a small fibre length and an own light source per fibre bundle. Then only the cables supplying power to a certain group are con¬ nected to the light source of that group from the control unit. The ligt fibre can also be fixed to the board by spray glue¬ ing or dimensioning the hole narrow for the fibre by crimp connection or, for instance, by melting fibre into the hole with a hot cutting blade while cutting off the fibre.

Claims: PATENT CLAIMS 1. A method to make a display board (8) illuminated by light fibres (11), in which method a display board illustrating different figures is produced by arranging the illuminating ends of light fibres into wanted spots onto the surface of the display board, characterized in that the - board is perforated by means of a coordinate controlled punching machine, - light fibre (11) is put by means of a movable feeding device into a punched hole (13) and threaded through it to a wanted length and cut off with cutting device (7,9) sub¬ stantially close to board (8) surface, - light fibre (11) feeding device is shifted over to the next hole (13). 2. A method according to patent claim 1 characterized in that light fibres illmuninated by the same light source ar cut off as short as possible and combined into fibre bundles on the board (8) underside, where light is steered to the fibres in the fibre bundle. 3. A method according to patent claims 1 and 2 characterized in that, for securing the cut off light fibres (11) into the hole (13), an adhesive film (10) fixed to the the board sur¬ face and to which the light fibre (11) adheres is used. 4. A method according to patent claims 1 and 2 characterized in that the light fibre is fixed by crimp connection to the hole in the board. 5. A method according to patent claims 1 and 2 characterized in that the light fibre is fixed by spray glueing to the hole in the board. 6. A method according to patent claims l and 2 characterized in that the light fibre is fixed to the hole in the board by heating/melting, for instance using a hot cutting device for cutting off the fibre. 7. A method according to any of the above patent claims 1 - 6 characterized in that for moving the punching, feeding and cutting device (4,5,6,7) on the bord surface a coordinate controlled transfer gear is used. 8. An apparatus to realize the method according to patent claim l characterized in that it contains a light fibre feeding device (4,5,14), a light fibre cutting device (7,9) and necessary means for making a hole (13) fixed to an attachment part (3) or a similar part controllably movable at the coordinate level. 9. An apparatus according to patent claim 8 characterized in that the hole (13) punching device can be used in place of the light fibre feeding and cutting device (6). 10. An apparatus according to patent claim 8 or 9 characteriz¬ ed in that it can be programmed to make punched figures in board (8) and to place light fibres of certain length into holes produced.

Inventors: HONGISTO AATTO, HONGISTO, AATTO
Applicants: HONGISTO AATTO, HONGISTO, AATTO
Application year: 1994
Main classification: G09F13
IPC codes: G02B6, G09F9, G09F13